<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  <!-- [html] 请写出唤醒拔打电话、发送邮件、发送短信的例子 -->
  <a href="tel:139xxxxxxxx">一键拨打号码</a>
<a href="mailto:yuojian@163.com">一键发送邮件</a>
<a href="sms:139xxxxxxx">一键发送短信</a>
顺便想起来 input 也有几个类型来影响键盘弹出的样式

<input type="text" placeholder="请输入文字"/>
<input type="number" pattern="[0-9]*" placeholder="请输入qq号"/> 
//type="number"限定输入数字，pattern="[0-9]*"限制数字范围
<input type="tel" placeholder="请输入电话"/>
<input type="date" placeholder="请输入日期"/>
<input type="datetime-local" placeholder="请输入时间"/>
</body>
</html>